Nice to meet you again here! faironx

If you have a lot of Steem power and Upvote a post, The post will be compensated more $0.01. And then, It will be actually rewarded $0.01 in account wallet within a week.

And, The promotion button needs Steem dollars for promoting a post, So, If you push the button, You will lost Steem dollars and They are gonna be burned. And then, the post will be placed the top of Promoted posts.

Most people don't usually use the promotion button. They just use bidding bots a lot rather than it.